Conventionally, a magnetic drive pump configuration is known that applies pressure on liquid by rotating an impeller by magnetic force.
With such a magnetic drive pump configuration, an impeller having an inner magnet (a driven magnet) is accommodated in a pump unit, and is rotatably supported via a non-contact bearing such as a magnetic bearing or a hydrodynamic bearing. Also, the impeller accommodated in the pump unit is not driven by a shaft coupled to a drive motor, but is indirectly driven while separated from a drive source, by the use of magnetic force (attraction force of the magnet).
Accordingly, a drive motor unit accommodating an outer magnet (a driving magnet) that rotates together with a drive motor is configured separately from the pump unit accommodating the impeller to which the inner magnet, which is to be attracted to the outer magnet, is attached. That is, the pump unit and the drive motor unit described above have separate casings, rendering a pump configuration according to which a coupling portion such as a drive shaft, for example, is not present in a drive mechanism for transmitting power for rotating the impeller.
By adopting the magnetic driving described above, an assembly configuration where the pump unit is inserted into a concave portion of the drive motor unit and the two are integrated by a screw or a detent is achieved, and this integrated configuration is referred to as a coupling pump configuration. In this case, the outer magnet is provided to a concave casing formed on the drive motor unit, and the inner magnet is provided to a convex casing formed on the pump unit.
Additionally, magnetic force in the direction of drawing the pump unit into the drive motor unit acts between the pump unit and the drive motor unit.
Furthermore, PTL 1 mentioned below discloses a blood pump which can be separated into a pump chamber and a magnet housing chamber so as to enable incineration of the pump chamber to thereby produce almost no ash. In this case, when a rotary body and a drive shaft in the magnet housing chamber are rotated, since the drive shaft is coupled to a rotating shaft by a joint, an impeller rotates together with the drive shaft and the rotating shaft. That is, according to the pump configuration disclosed in PTL 1, an impeller inside the pump chamber is coupled to a drive unit inside the magnet housing chamber by a shaft.